diff --git a/main/ble.c b/main/ble.c
index b079241..f04f241 100644
--- a/main/ble.c
+++ b/main/ble.c
@@ -45,6 +45,7 @@ static event_callback_handle_t callback_handlers[CONFIG_CACO_MAX_SERVICES] = { 0
 
 static int ble_gap_event(struct ble_gap_event *event, void *arg);
 static int ble_svc_access(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt *ctxt, void *arg);
+static int svc_access_system(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt *ctxt, void *arg);
 
 static int barback_ble_char_access(uint16_t conn_handle, uint16_t attr_handle, struct ble_gatt_access_ctxt *ctxt, void *arg);